i am just looking for away to free up some range and spl for my 9512 as far as power handling and excursion i will ever use it all.i simply want a horn that will help load between 50-80 hzs. then I can tune to 35-40 hzs. I have modded the pi folded corner horn to give me the dimensions that i want i just want to know how to generally predict its responce. Also if the box is peaky at the certain frequency i have a ten band eq to use on it. when i get the boxes upload i will post them. some have longer horn, larger vented enclosures smaller, vented enclosures but try tried to keep the horn flare the same. first